Show "good match" tracks in the main "related track" display.

I think the current way that "good match" tracks are displayed is unnecessarily cumbersome. I think it would be much more useful to just mark these tracks with an appropriate colour in the main "related track" listing.

And while this is technically another request, it's related so i'll leave it here: Add an "allow good match tracks to override search criteria" checkbox in the related tracks configuration panel.